1. Field of the Invention
The invention relates to a method and device for a discharge of a filter cake, loosened from filtration elements, out of a filter vessel of a filter apparatus, more particularly, out of a high pressure continuous filter device.
2. Description of the Related Art
Such a method and device is known, in which a loosened filter cake is discharged from an over-pressured filter vessel by means of two conveyor screws which adjoining each other at an angle of 90 degrees. The second conveyor screw, which debouches out of the filter vessel, along with the more or less compressed filter cake forms a closure between the inner-side and the outer-side of the filter vessel while under pressure, so that only the filter cake will be transported outside by the second conveyor screw and no pressure-loss will occur in the filter vessel itself.
This known method has the drawback that, with certain types of cake compositions, the cake in the second conveyor screw no longer is transported outside, but starts to turn along with the conveyor screw.
Also in this known method and device, certain types of cake composition generate an inadmissibly high wearing of the blades of the conveyor screws, causing the necessity to replace them quickly and repeatedly.
The invention aims to obviate the drawbacks of the known method and apparatus for discharge of a filter cake, loosened from filter elements, out of a filter vessel of a filter apparatus, more particularly, out of a high pressure continuous filter apparatus.